buildgcc: Update and fix GDB

GDB stopped building ever since we updated from version 7.6
but nobody noticed ;)
Update from 7.9 to 7.9.1 and bring the required patches forward.

Change-Id: I2f357525a46d5540e9f57b80d830943bbd5dfcaf
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: http://review.coreboot.org/10494
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <edward.ocallaghan@koparo.com>

util/crossgcc/patches/gdb-7.6_no-texinfo.patch

@@ -1,14 +0,0 @@
-diff -ur gdb-7.6.orig/missing gdb-7.6/missing
---- gdb-7.6.orig/missing	2009-08-22 04:48:33.000000000 -0700
-+++ gdb-7.6/missing	2013-07-10 13:10:32.940902728 -0700
-@@ -314,8 +314,8 @@
-     fi
-     # If the file does not exist, the user really needs makeinfo;
-     # let's fail without touching anything.
--    test -f $file || exit 1
--    touch $file
-+    #test -f $file || exit 1
-+    #touch $file
-     ;;
- 
-   tar*)

util/crossgcc/patches/gdb-7.9.1_no-doc.patch

@@ -0,0 +1,12 @@
+diff -ur gdb-7.9.1/gdb/Makefile.in gdb-7.9.1/gdb/Makefile.in
+--- gdb-7.9.1/gdb/Makefile.in	2015-05-13 10:36:05.000000000 -0700
++++ gdb-7.9.1/gdb/Makefile.in	2015-06-09 13:22:53.594505278 -0700
+@@ -1065,7 +1065,7 @@
+ 
+ TSOBS = inflow.o
+ 
+-SUBDIRS = doc @subdirs@ data-directory $(GNULIB_BUILDDIR)
++SUBDIRS = @subdirs@ data-directory $(GNULIB_BUILDDIR)
+ CLEANDIRS = $(SUBDIRS)
+ 
+ # List of subdirectories in the build tree that must exist.

util/crossgcc/patches/gdb-7.9.1_pythonhome.patch

@@ -1,8 +1,8 @@
-diff -ur gdb-7.6/gdb/python/python.c gdb-7.6.patched/gdb/python/python.c
---- gdb-7.6/gdb/python/python.c	2012-06-25 18:53:20.000000000 +0200
-+++ gdb-7.6.patched/gdb/python/python.c	2012-10-24 15:28:37.422047.69 +0200
-@@ -1227,6 +1227,15 @@
- 			     SLASH_STRING, "python", NULL));
+diff -ur gdb-7.9.1/gdb/python/python.c gdb-7.9.1.patched/gdb/python/python.c
+--- gdb-7.9.1/gdb/python/python.c	2015-05-13 10:36:05.000000000 -0700
++++ gdb-7.9.1.patched/gdb/python/python.c	2015-06-09 13:13:24.824178760 -0700
+@@ -1681,6 +1681,15 @@
+ #endif
  #endif
  
 +  char readlinkbuffer[BUFSIZ];